The Acer S1213 supports a maximum resolution of 1920 x 1200 (WUXGA). That's over seven times the resolution of the most common graphics resolution of 640 x 480 (VGA). In addition, this projector supports a graphics resolution of 1024 x 768 (XGA).
A 1920 x 1200 (WUXGA) graphics resolution is in fact the best supported resolution across all data projectors of a comparable age and type to the S1213.
Across comparable types of projector the worst supported resolution is 640 x 480 (VGA).